


The Fall of Summer

by bladeofthestars



Category: Gravity Falls
Genre: But probably not in at least the first five chapters, F/F, I'm sorry for being billdip trash, M/M, Not noncon but considering that they're minors I guess it's technically dubcon?, Not really sure what I'm doing here, Probably some underage, Slightly aged up Pines twins, Tags will change as I figure out exactly what I'm doing, Will probably have billdip and mabcifica
Language: English
Status: In-Progress
Published: 2015-07-29
Updated: 2015-08-01
Packaged: 2018-04-11 20:53:24
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings, Underage
Chapters: 3
Words: 3,372
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/4451966
Author URL: https://archiveofourown.org/users/bladeofthestars/pseuds/bladeofthestars
Summary: <blockquote class="userstuff">
              <p>Dipper and Mabel are in Gravity Falls for their third summer in a row now. The only problem is, it doesn't really feel like summer. With the wildlife going nuts, crazy weather patterns, and a mysterious woman on the loose, the Mystery Twins are going to have to give it their all to crack this case before anything worse can happen. Just how far are they willing to go for the small town?</p>
            </blockquote>





	1. Fallen Leaves

**Author's Note:**

> So, it's Dipper and Mabel's third summer in Gravity Falls. When Stanford came out of the portal two years ago, he'd told Stanley to get out by the end of the summer. He hadn't counted on being sucked into adventures with Stanley and his niece and nephew. In my story, they've worked things out and are living together pretty much peacefully, though there's still some hurt between them that's going to take an awful lot of time to fix.  
> I'm not sure where I'm going with this story. I think I want it to take on a darker bent at some point, though the first few chapters I've worked on so far have been fairly bright and upbeat. School starts again soon for me, but until then, I'll try to post as much as I can. The first few chapters are going to be pretty short, sorry!  
> Feel free to comment, tell me about anything you do/don't like and/or want to see happen!

A cool breeze whips through Gravity Falls and with it, fallen leaves. They dance in the wind, whirling in captivating patterns. Only last week there’d been a big heat wave but now the town’s residents were walking around in scarves and jackets.  
  
Dipper and Mabel groan as they look out the window of their bedroom. Despite all the pine trees in the Oregon town, there’s still a lot of bright colors patched throughout the forest.  
  
“I appreciate it not being so hot any more, but now it just feels… depressing out.” Dipper hangs his head.  
  
“I know! It feels like we should be heading back to school…” The two hear an oink and look towards it in unison. Waddles the pig blinks at them blankly as he shoves an apple in his face.  
  
“He’s been eating like, three times as much as normal lately, Mabel.”  
  
“I don’t know what to do about it, but I do know Grunkle Stan is gonna find out soon and he won’t be happy.”  
  
The two look out the window and sigh before turning to head downstairs.

  


“There you are!” their Grunkle greets them as they walk into the gift shop area of the Shack. “Dipper, Mabel, rake the lawn before the tourists start showing up. Here.” He roughly thrusts rakes and garbage bags at them, which they take and head out.  
  
“That’s… weird. Stan doesn’t usually send you out to do the physical labor with me.”  
  
Mabel just shrugs noncommittally. Then she positively lights up. “Do you wanna play in the big leaf piles before we throw them away?”  
  
Her eyes glitter and there’s no way Dipper can say no. Not that he wanted to, anyway.  
  
They rake and they rake. The property around the Shack is enormous. Once they’ve gotten all the leaves together, they take turns jumping and rolling around in the leaves. Even Waddles joins in, though Mabel drags him out when he decides their leaf pile is a perfect place for a nap.  
  
Another strong, brisk breeze sweeps through, catching a good portion of their leaf pile. The leaves don’t just float off the pile gently to be easily raked back in. They hang in front of the twins’ faces almost teasingly before landing halfway across the lawn. Mabel lets out a groan and starts to go after some of them before Dipper grabs her.  
  
“Mabel, look!”  
  
At the edge of the trees, a statuesque woman glides forward, keeping to the shadows. Her long hair flows behind her, adorned with many beautiful leaves. Her dress looks almost like fire, made only of the brightest maple leaves. A few forest critters trail in her wake, seemingly entranced with her. Dipper and Mabel gape at her slow procession.  
  
She turns to meet their gaze and her eyes are like liquid onyx. A smile quirks her lip before she sweeps along, disappearing quickly.  
  
“Woah, did you see her Dip-dop?!” Mabel shouts at her brother, who flinches because she was standing rather close to him. “She was _beautiful_.”  
  
Dipper nods, unphased by his sister’s enthusiasm.  
  
“I think she might have been supernatural.”  
  
“I think she might have been a super model.”  
  
“No, really Mabel. Something was really off about her. Maybe the journal has something about it…”  
  
Dipper pulls the ever-present journal out of his vest and starts to distractedly walk off. It isn’t until he’s out of sight that Mabel realizes, with a sigh, that all of the leaves still have to be bagged.  
  
“Grunkle Staaaaan! We should charge people to jump in this leaf pile, it’s amazing!”


	2. Sugar Beets- Indicator species of the coming apocalypse?

**Notes for the Chapter:**

> Again, a small chapter. They should start to get longer from here on out.

_“Farmers across Oregon are baffled as crops that would usually mature late in the season -not harvested until at least September- are already maturing and ready for harvest. We now cut to our field reporter, Elaina Farkan, who is live with a local farmer. Elaina?”_  
  
_“Thanks, Gary. I’m here with Bob Johnston, a local farm owner. Bob, what can you tell us about this?”_  
  
_“It’s not natural. Sugar beets and sweet corn have **never** been ready this early before, I don’t even think they’ve been in the ground long enough to be mature, but everything’s ripe and ready. The weather lately hasn’t made sense either-“_  
  
“Boring.” Grunkle Stan grunts as he flips through the television channels. He finally settles on a rerun of Duck-tective.  
  
“What was that report saying, Stanley?” Grunkle Ford calls out from the kitchen.  
  
“Nothing interesting, just some farmer going on about how they harvested early or something.”  
  
Grunkle Ford scratches his chin thoughtfully. He was digging through what he knew about the supernatural off-hand, trying to remember if he knew something capable of maturing plants rapidly, when his niece and nephew came bursting into the kitchen.  
  
“Grunkle Ford, you’re making dinner tonight, right?”  
  
Ford absently nods at Dipper.  
  
“Can we help? Pleeeease?” Mabel asks him, eyes wide and shining.  
  
“Uh, sure, I don’t see why not-“  
  
  
“YAAAAAAY!” Mabel pulls an industrial sized tub of glitter out of God only knows where as Dipper gets out a camcorder.  
  
“Episode One of _In the Kitchen with Grunkle Ford_ is a go!” Dipper cries, momentarily zooming in on the tub of glitter, which Ford had noticed had the word “Edible” on it. He runs a hand down his face, schooling his features before turning to the twins.  
  
_How Stanley deals with these two all summer, every summer, I don’t know…_  
  
“Alright, what should we make…”

~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~

“Nnnnyaaaargh! I can’t find anything about her anywhere!” Dipper slams his journal on the bed next to him before huffing and falling back on his pillows harshly.  
  
“Did you ask Grunkle Ford if he knew anything?”  
  
“Yes, and he said the same thing you did. Probably some weird woman or somebody on their way to a fashion show. Mabel, you know my instincts about these things are usually right. Remember Norman?”  
  
“You thought he was a zombie!”  
  
“Yes, but I _did_ know he wasn’t human, at least.”  
  
“That’s true…. Dipper, I hate to say it, but I don’t really think there’s much we can do unless she shows up again.”  
  
Dipper sighs. “I know… I was actually thinking of wandering around the woods a little tomorrow to see if I could run across her. Do you wanna come with?”  
  
“Yeah! We can go all Mystery Twins on this!”  
  
“Mystery Twins…” Dipper smiles as he shifts in his bed to get more comfortable. It really did seem like if he and Mabel combined forces, they could solve anything Gravity Falls threw at them.  
  
As he drifts into unconsciousness, he doesn’t notice the being that slips in, unhindered.  
  
A certain dream demon makes its way through the hallways of Dipper’s brain. His black hands trail over the surfaces of doors and walls lovingly as he makes his way to the newest section. While he’s got enough windows to always be watching the Mystery Shack and his favorite meatsack, sometimes things come up, and he misses something important. But hey, there’s nothing quite like taping your favorite show to watch later, especially when you get the nitty gritty first person view version when you have to wait.  
  
Bill shuffles through doors, briefly chuckling at an image of Ford groaning with glitter around his mouth before shutting that door and moving on to the next. He almost shuts the door on the leaf pile memory as well before the woman shows up.  
  
“Well well well, what do we have here?”  
  
He watches her stride at the edge of the woods, he feels the tingle that goes down Dipper’s spine when she locks eyes with him.  
  
“I haven’t seen one of her kind in forever.”  
  
Bill lingers a little longer, watching Dipper search for information in frustration.  
  
“Maybe I’ll stick around for this one.”


	3. She Wants the D! ...And the M Too, Actually

**Notes for the Chapter:**

> Chapter Three! A note on the topic of Bill: While he seems to prefer his original triangular digs, he's capable of taking on pretty much any form he can think of. It *is* the Mindscape, after all. He does not, however, seem capable (or perhaps he's just not willing) of losing the black and gold color scheme.

Dipper and Mabel traipse through the woods happily, searching for their mystery woman, but also just enjoying the time outdoors after being cooped up in the Shack for too long. It was traditional at this point for them to work for their grunkle every summer, and Stan was really taking advantage of it this year. Soos and Melody had finally gotten married and were on their honeymoon until the end of the month, leaving the Shack a bit shorthanded. Ford refused to have anything to do with the Shack, preferring to continue with his supernatural research, albeit a bit more carefully than he had been thirty years ago.  
  
Mabel shifts her backpack around, trying to distribute the weight better. They’d packed food, water, flashlights, bits of rope, and Mabel had brought her trusty grappling hook. They weren’t sure how long they’d be in the forest when they had packed, and with the way Gravity Falls tends to be, it was better to be prepared.  
  
“Do you think next time we do something like this, Pacifica can come?” Mabel asks a little uncertainly, not sure if their hike was intended to be a twins only activity.  
  
“Oh yeah, I forgot Paz was back from Spain. She can totally come, as long as her parents don’t try to sue us or something if her clothes get dirty.”  
  
Mabel shoves her brother. “Dipper! You know it’s not like that anymore!”  
  
“I know it’s not!” Dipper says with a laugh.  
  
It really wasn’t. While Preston Northwest was still a shrewd businessman, he wasn’t the hard-ass he used to be. Having a few near-death experiences can really change a man, even more so when shared with your loved ones. Gone were the days of a family trained to respond to the tinkling of a bell, and so too were the days of fraud and theft. There were still important meetings and fancy parties (and likely always would be), but Pacifica was now her parents’ number one priority, as she should be. The Northwests had decided that the best thing for their daughter was lesson by example and hands-on experience.  
  
That was how Pacifica had ended up in Spain for the last half of the school year and the first few weeks of the summer. Her parents had given her a list of languages and told her to pick one to learn. All were important in the business world. Pacifica had picked Spanish because she’d already learned some in school. She and her family had then gone to Spain, with Pacifica in an exchange program while they dealt with some of their European connections.  
  
Dipper had grown to actually like the girl, though he wasn’t nearly as attached to her as Mabel was. She spent a lot of time with both twins, sometimes even flying down to Piedmont for a weekend here and there during the school year. It had been a little lonely without her around for the past few months, though Mabel Skyped her often and Dipper would sometimes join in.  
  
The twins continue their walk almost haphazardly, chit-chatting brightly without an awful lot of regard to their surroundings. Dipper knows they won’t get lost, but he doesn’t think about the possibility of something unwanted finding them. Neither of them notice the occasional odd, triangular shadow in their peripheral vision.  
  
They decide to break for lunch in a rather large, beautiful clearing. There’s a small pond fed by a murmuring brook. The pond has all manners of lily pads across its surface, most of them in bloom. The twins settle in soft grass that’s filled with wildflowers. They sit and munch happily on simple sandwiches.  
  
A small breeze sweeps through the clearing. A few red leaves flutter madly in it. Something rustles in the brush and Dipper leaps to his feet, automatically moving to place himself between the source of the noise and his sister. Mabel gets up as well, carefully putting her back to Dipper’s in case the rustling brush was a diversion for a sneak attack. Paranoid, both twins briefly scan the sky for threats as well.  
  
Mabel feels Dipper breathe in sharply and she turns. Three stags walk out of the brush slowly. Their antlers are bloody, like they might have gored someone, and Mabel briefly worries until she realizes that the clumps hanging from the points are velvet. Then she worries anew because deer tend to shed their velvet around the same time of year as they go into rut, and they get extremely testy during rut.  
  
“Don’t worry; they’re not going to hurt you.”  
  
The woman from the day before smoothly glides out of the brush behind the stags. Up close, she’s even more beautiful than either of them had previously thought. Her solid black eyes are a little unsettling, but the shine of her auburn hair is more than enough to distract from them. Both twins are taken with her ethereal beauty, enough so that Dipper almost forgets he came out to investigate the woman in front of him.  
  
“What _are_ you?” Dipper finally manages.  
  
“That’s a little rude, don’t you think?” she asks him in a teasing manner. He shudders nonetheless, feeling the implied threat of _don’t ask again or else._  
  
“I’m sorry, miss. My brother here isn’t the best with his words and only meant that surely someone as beautiful as you couldn’t be human.” Mabel gracefully stepped in to save the conversation before it could go any further downhill.  
  
The woman flutters unusually long, dark eyelashes at them.  
  
“Thank you, dear. I’m quite taken with the two of you as well. The people around here don’t seem to notice me directly like two have.”  
  
She steps closer, and neither of them feel particularly inclined to shrink from her advance. She smiles, revealing sharp teeth, and steps even closer. She brushes the hair back from Dipper’s forehead, gazing admiringly at his birthmark, and runs her other hand through Mabel’s long tresses.  
  
“How would you two like to live with me?” she whispers sweetly. “Live forever in forests of red and gold and purple with all of the creatures of the forest as your best friends?”  
  
Mabel thinks of hanging out with a troupe of squirrels while Dipper’s mind immediately jumps to having a trusted stag as his mount. They both nod almost immediately, mouths gaping slightly. She smiles again, gently patting both of their heads before reaching down to take their hands.  
  
“Hey hey hey _woah!_ Back off, sister!”  
  
In a burst of blue flame, all of the color drains from the world and Bill Cipher materializes in the clearing. With a strange, almost electronic sound, he swishes a cane into existence and begins fiddling with it.  
  
“Why don’t you go find some saplings of your own? These two Pines belong to _me._ ”  
  
“ _Cipher!_ ” the woman bares her teeth and hisses at the dream demon. She quickly drops her hands away from the twins and whirls away.  
  
“This isn’t the last you see of me!” she spits over her shoulder as she sweeps back off into the forest, followed closely by her stags.  
  
Bill watches her for a moment before turning to the twins. Dipper groans a little before shaking his head. Mabel’s jaw finally shuts. The two seem to be breaking out of the daze the woman had put them under pretty well.  
  
“Bill?”  
  
Bill turns to his Pine Tree. His face scrunches adorably as he obviously tries to figure out what just happened.  
  
“What’d you do to us, Bill?”  
  
“I just saved you from that autumn nymph, kid.”  
  
Bill zooms in close to the two and ruffles their hair, carefully covering the nymph’s magical residue in his own. Not that the kids needed to know he was basically doing the demon equivalent of scent marking.  
  
“What do you mean, ‘saved us’?” Mabel asks, sounding like she’d just woken from a nap.  
  
“Do you not remember? She practically had the two of you by the arm, ready to drag you off who knows where because you agreed to live with her. Sheesh, you meatbags have fragile memories.” He morphs into a rather lanky human form and floats lazily on his back in front of them. “You see a pretty face and suddenly all bets are off.”  
  
Dipper frowns. The longer the woman –what had Bill called her, a nymph?- was gone, the clearer his thoughts were getting. He knew she was trying to take them and figured she must have worked some sort of spell to get them in such a daze. What he didn’t know, however, was why Bill had chosen to step in. Bill had helped them in the past occasionally, but his style tended to be more vague hints and riddles than it was outright muscling another creature away from the twins.  
  
The creature was also not above incapacitating them if they tried to interfere with his own plans, though he did seem like he tried to do things less painfully, nowadays. No, the demon had become almost an ally to the twins, but Dipper still couldn’t figure why he would act so protectively on their behalf. A throat being cleared breaks his reverie.  
  
“A ‘Thank you for saving my life O great and powerful Master Cipher’ or at least a ‘Wow, you’re great, Bill!’ would be _nice._ ” the demon says, pouting.  
  
“Thank you, Bill.” the twins say in unison.  
  
“Yeah, thanks for saving us from… living with a nymph?” Mabel questions.  
  
“She wanted both of you for lovers-”  
  
Dipper chokes on his spit, but Bill continues.  
  
“-And I figured, you meatbags usually like to be in your right mind before you consent to being with someone for the rest of eternity, right? Thought I’d do you a favor and step in. A bit unfair of her to use a glamour like that, in my opinion-“  
  
“You thought you’d do us a _favor?_ ” Mabel scoffs at the very thought of Bill doing something for nothing.  
  
“I, err-“ Bill knows he’s been backed into a bit of a verbal corner and decides to go for broke. “I mean, the term _favor_ is relative since you humans don’t ever really do each other favors for the sake of being nice. Rest easy knowing you owe me one!”  
  
With that, Bill’s form sucks into itself with a popping noise and the twins find themselves waking up.  
  
“I really don’t like the idea of owing Bill anything.” Mabel says, rubbing bits of drool and grass off her face.  
  
“Me either, but we don’t really have a choice. I guess we should be glad it’s just a favor and not a deal. …Mabel, do you remember Bill telling the nymph we were ‘his’?”  
  
Mabel furrows her brow. “Now that you mention it, yes. What do you think he meant by that?”  
  
“I don’t know, but it doesn’t sound good.”  
  
The twins walk home in somber silence, trying their best not to get in any more trouble on the way. Their mood is still deadly serious when they get back to the Shack and tell their grunkles what happened in the forest.  
  
Stanley and Stanford are both alarmed by Bill’s wording, but only Stanford is interested in the appearance of the autumn nymph.  
  
“She might be responsible for the weird weather patterns we’ve been having, and the out of season crop maturation. It’s too early to really say anything for certain, but those are things that autumn nymphs are supposed to preside over.”  
  
Dipper nods, fascinated as he takes notes. He’s already sketched the nymph they met in the woods and is now in the process of finding any and all information about her that he can. He wants to be prepared if they bump into her again.  
  
“Grunkle Ford, do you know how to protect against glamour charms?”  
  
“Well kid, that’s another fascinating and fairly complicated topic. Back in the day, I dabbled in magic a bit and I must say, it’s not for everyone. Some people can’t seem to handle the energy drain. I could try teaching you a little, if you’d like, but we’ll have to stop if it seems like you’re not cut out for it.”  
  
Dipper nods, eager. He can’t believe he’s never asked Ford this sort of thing before.  
  
“How does tomorrow sound?”  
  
“Great!”  
  
“Alright, kiddo.” Ford claps him on the shoulder as he walks off into the kitchen.  
  
Dipper bounces on his heels and holds back a squeal of excitement. He can’t _wait!_


End file.
